|Have you done a Port Scan on your WAP? |
It sounds like it has ports 25 and 110 are closed.
If you cant ping then it sounds like these WAPs are also routers and are screwing up the routing tables. You may need to change their roles to just Access Points.
Are there two different subnets for the WiFi and the LAN?
We need a hole lot more information. To start give us an IPCONFIG while on the LAN and one while on the WIFi.
You may want to hide the first two octets for security reasons, we just need the network and mask information.